The present invention relates generally to the manufacturing of electrical ccmponents and specifically to an automated lead forming system for axial electrical components.
The fabrication of printed circuit boards often includes the forming of wire-like leads of axial components. This "forming" step includes the cutting of the leads to a specific length, and the bending of the leads into a tailored configuration, using axial forming equipment.
Setup and adjustment of axial forming equipment is currently a labor intensive manual operation. Lead forming equipment is configured to operate with one set of dies that are dedicated to a specific lead shape and range of diameters. Each different lead shape or range of lead diameters require a die change involving shutting the machine down, determining and retrieving the proper die set from tool cribs, and removing and replacing the dies. Changes in lead center to center spacing require shutting the machine down, loosening dies, and manually adjusting their positions. These characteristics of currently available equipment require large lot sizes for cost-effective operation. Present ccmponent forming methods will be incompatible with the robotic and automated assembly techniques being developed for modern assembly plants.
The task of automating axial lead forming is alleviated, to some extent, by the following U.S. Patents, which are incorporated herein by reference
U.S. Pat. No 3,147,779, issued to B. Brown on Sept. 8, 1964; PA0 U.S. Pat. No. 3,993,108, issued to Kirschenman et al on Nov. 23, 1976; PA0 U.S. Pat. No. 3,945,408, issued to Halligan on Mar. 23, 1976; PA0 U.S Pat. No. 4,072,177, issued to Daebler on Feb. 7, 1978; PA0 U.S. Pat. No. 4,203,477, issued to Bruller et al on May 20, 1980; and PA0 U.S. Pat. No. 4,447,945, issued to Priscsak on May 15, 1984.
All of the above references disclose lead forming machines, with various degrees of automation. For example, the Bruller et al reference discloses an apparatus that automatically cuts and clinches leads which are extended through a circuit board. The Halligan reference discloses an apparatus for automatically forming and trimming the lead wires of transistors and like electrical components, which have a plurality of leads extending from a potted body.
While the references cited above enhance mass production, some degree of manual operation is retained by all of them. The degree of manual operation retained in these references ranges from the initial setting of dies to constant supervision.
In view of the foregoing discussion, it is apparent that there currently exists the need for a programmably adjustable lead forming system, with die settings that are adjustable by computer control. The present invention is intended to satisfy that need.